A non-invasive sensing method to estimate abdominal pressure by electromyography in urodynamics study

Ambulatory urodynamics study has the potential to provide measurements of bladder function during activities of daily living. Conventional rectal catheters, which are used for the measurement of abdominal pressure, can cause erroneous results which affect the detrusor pressure, and the catheter itself is not comfortable for the patients. To reduce these problems, we invented a new method of measuring the abdominal pressure in a non invasive manner using the surface electromyographic (EMG) signals of the rectus abdominis muscle. The correlation coefficient and root mean square error (RMSE) between the measured abdominal pressures measured by conventional rectal catheters and those estimated by our proposed algorithm were 0.79±0.06 and 0.10±0.07, respectively. These findings suggest that the surface EMG of the rectus abdominis muscle might be able to be used indirectly for the measurement of the abdominal pressure in ambulatory urodynamics monitoring studies.